Merge pull request #245 from QuantEcon/review_lectures

Review lectures

Author: jstac

lectures/long_run_growth.md

@@ -33,7 +33,7 @@ In a nutshell, this lecture records growth trajectories of various countries ove
 
 While some countries have experienced long term rapid growth across that has lasted a hundred years, others have not. 
 
-Since populations differ across country and within a country vary over time, it will
+Since populations differ across countries and vary within a country over time, it will
 be interesting to describe both total GDP and GDP per capita as it evolves within a country.
 
 First let's import the packages needed to explore what the data says about long run growth
@@ -56,7 +56,7 @@ some dating back to the first century.
 
 The data can be downloaded from the [Maddison Historical Statistics webpage](https://www.rug.nl/ggdc/historicaldevelopment/maddison/) by clicking on the "Latest Maddison Project Release". 
 
-For convenience, here is a copy of the 2020 data {download}`in Excel format <datasets/mpd2020.xlsx>`.
+For convenience, here is a copy of the {download}`2020 data <datasets/mpd2020.xlsx>` in `Excel` format.
 
 Let's read it into a pandas dataframe:
 
@@ -91,7 +91,7 @@ cntry_years
 
 Let's now reshape the original data into some convenient variables to enable quicker access to countries time series data.
 
-We can build a useful mapping between country code's and country names in this dataset
+We can build a useful mapping between country codes and country names in this dataset
 
 ```{code-cell} ipython3
 code_to_name = data[['countrycode','country']].drop_duplicates().reset_index(drop=True).set_index(['countrycode'])
@@ -153,7 +153,7 @@ _ = gdppc[cntry].plot(
 [International Dollars](https://en.wikipedia.org/wiki/International_dollar) are a hypothetical unit of currency that has the same purchasing power parity that the U.S. Dollar has in the United States at any given time. They are also known as Geary–Khamis dollars (GK Dollars).
 :::
 
-We can see that the data is non-continuous for longer periods in the early part of this millennium, so we could choose to interpolate to get a continuous line plot.
+We can see that the data is non-continuous for longer periods in the early 250 years of this millennium, so we could choose to interpolate to get a continuous line plot.
 
 Here we use dashed lines to indicate interpolated trends
 
@@ -291,13 +291,13 @@ plt.show()
 ```
 
 
-The preceding graph of percapita GDP strikingly reveals how the spread of the industrial revolution has over time gradually lifted the living standards of substantial
+The preceding graph of per capita GDP strikingly reveals how the spread of the industrial revolution has over time gradually lifted the living standards of substantial
 groups of people  
 
-- Most of the growth happened in the past 150 years after the industrial revolution.
-- Percapita GDP's in the UK and the US, on the one hand, and in China, on the other, diverged from 1820 to 1940.
-- The gap has closed rapidly after 1950 and especially after the late 1970s.
-- These outcomes reflect complicated combinations of technological and economic-policy factors that students of economic growth try to understand and quantify
+- most of the growth happened in the past 150 years after the industrial revolution.
+- per capita GDP in the US and UK rose and diverged from that of China from 1820 to 1940.
+- the gap has closed rapidly after 1950 and especially after the late 1970s.
+- these outcomes reflect complicated combinations of technological and economic-policy factors that students of economic growth try to understand and quantify.
 
 
 It is fascinating to see China's GDP per capita levels from 1500 through to the 1970s.
@@ -306,10 +306,10 @@ Notice the long period of declining GDP per capital levels from the 1700s until
 
 Thus, the graph indicates 
 
-- A long economic downturn and stagnation after the Closed-door Policy by the Qing government
-- China's very different experience than the UK's after the onset of the industrial revolution in the UK
-- How the Self-Strengthening Movement seemed mostly to help China to grow
-- How stunning have been the growth achievements of Modern Chinese economic policies by the PRC that culminated with its late 1970s Reform and Opening-up
+- a long economic downturn and stagnation after the Closed-door Policy by the Qing government.
+- China's very different experience than the UK's after the onset of the industrial revolution in the UK.
+- how the Self-Strengthening Movement seemed mostly to help China to grow.
+- how stunning have been the growth achievements of modern Chinese economic policies by the PRC that culminated with its late 1970s reform and liberalization.
 
 ```{code-cell} ipython3
 ---
@@ -363,11 +363,11 @@ plt.show()
 We can also look at the United States (USA) and United Kingdom (GBR) in more detail
 
 In the following graph, please watch for 
-- impact of trade policy (Navigation Act)
-- productivity changes brought by the industrial revolution
-- how the US gradually approaches and then surpasses the UK, setting the stage for the ``American Century''
-- the often unanticipated consequences of wars 
-- interruptions and scars left by {ref}`business cycle<mc1_ex_1>` recessions and depressions
+- impact of trade policy (Navigation Act).
+- productivity changes brought by the industrial revolution.
+- how the US gradually approaches and then surpasses the UK, setting the stage for the ''American Century''.
+- the often unanticipated consequences of wars.
+- interruptions and scars left by [business cycle](business_cycle) recessions and depressions.
 
 ```{code-cell} ipython3
 ---
@@ -527,7 +527,7 @@ ax = worldgdppc.plot(
 )
 ```
 
-Looking more closely, let's compare the time series for `Western Offshoots` and `Sub-Saharan Africa` and more broadly at a number of different regions around the world
+Looking more closely, let's compare the time series for `Western Offshoots` and `Sub-Saharan Africa` and more broadly at a number of different regions around the world.
 
 Again we see the divergence of the West from the rest of the world after the industrial revolution and the convergence of the world after the 1950s